Valve-seating tool



Jung 4, 1929. H, c, FUHWAN 1,715,546

' VALVE SEATING TOOL Filed Sept. 2'7, 1926 bon almost as hard as glass.

1 Patented June 4, 1929.

UNITED :STATES' HERMAN c. FUHRMAN, or MARION, IOWA.

PATENT OFFICE.

I VALVE-SEATING TOOL.

Application fil'e'd September 27, 1926. Seria1'No.'137,9l0.

This invention relates to the dressing. of gasoline engine valve seats, and the ob ect of the invention is to vprovide a tool whereby a faulty valve seat may be prepared for grinding, or the cutting action of a fine reamer.

In most cases the valve-seats of explosion at the proper angle for the seat. The work,

however, is very injurious to the reamer, as it dulls the edges rapidly, when the reamer must be reground. Thisis a nice and slow operation, and can only be done in a special grinder fitted for the purpose.

This invention aims to dispense with the reamer in some cases, and in all cases where its use is necessary,to save the cutting edges and prolong the usefulness of the reamer by removing the glassy scale and leaving for the work of the reamer only clean iron.

In the accompanying drawing, forming a' part of this specification, Fig. 1 is a side ele-' vation of a tool embodying my invention as in use, the valve seat being shown in section. t

Fig. 2 is a plan view of the tool as seen from below. Fig. 3 is a section of the same to the right of the line '33 of Fig. 1.

In the drawing, the numeral 5 denotes a fragment of an engine block containing the valve-seat 6. A guide 7 for the stem of a valve is herein shown as a'bushing. These vary in diameter, and any reaming tool intended for general work will'n'eed a set of r spindles 8 with shafts varyingin diameter to fit the various valve guides. It is contemplated that the spindle for this toolwould also serve for a reamer as well.

The spindle carries a conical head 9,suitably attached, as by a nut 10. The conical face of the head corresponds to the angle of the valve and seat. Parallel with this face are bored anumber of seats 11 for scrapers 12, The seats, which are preferably cylindrical, open with a narrow slot outwardly, so that the scrapers set therein project a lit But in and adapted to tle beyond the conical surface, and are thus adapted to bear on the valve-seat as the tool. 7

is turned. The scrapers, as herein shown, V are cylindrlcal sectlons of roughened and L hardened steel, correspondingly practically to sections of rattail files. They are secured in place by set screws lii having tapered heads, as shown in Fig. 3. i

It will'be evident that a few turns of the tool when in the position shown in Fig. .1,

will by abrasion quickly remove the glassy carbonized surfaces of the valve seats, but

the faceof the head will prevent thes'crapers from digging into the seat between such'hard spots and making a wavy, uneven surface. Once the hard scale is removed the seat may be finished, by grinding the valve and seat directly, or by truing with a cuttingreamer before the grinding operation. v

The roughened bits or scrapers being made fast1nthe1r seats, their action is a posltlve abrasion by scrapmg. The bits may be tempered very hard, so as topeel off the hardest 'scale that may form on the valve-seat. When they dull, as of course they will in time, fresh abrading surfacesmay be brought to bear on the work by turning the bits, sliding them' endwise, or reversing them. ,When finally worn out they are. replaced by new ones, at e a trifling cost.

I claim:

1. A valve-seat tool, comprising a spindle with a shaftfitting revolub'ly in the valve- 1 stem guide, a head attached to the spindle,

and having cylindrical radial bit-iseats with solid backs formed in the body, of thehead, the seats opening outwardly their full length in narrow gaps to permit a slight projection l of the bits, and straight, cylindrical and re- 7 U versible roughened bits. mounted, immovably in said seats.

2.1n a valve-seat tool, a' spindle fitted to revolve in the valve-stem guide, a frustroing cylindrical radial seats for abrading bits opening outwardly their full length in narconical head secured to the spindle, and havformed in thesolid body of the head, and 7 row gaps to permit a slight projection of the.

peripheries ofthe hits, a series of cylindrical,

reversible, rough-faced bits set in saidseats,

and conical set-screws disposed in the head press the bits outwardly into saidgaps.- i i f In testimony whereof I alfix my signature.

HERMAN C. FUHRMAN. 

